This application is submitted to NIAAA in response to Program Announcement 08-167 Secondary Analysis of Existing Alcohol Epidemiological Data which was created to support "studies that more fully utilize currently available data sets to increase our understanding of the incidence, prevalence and etiology of alcohol related problems and disorders in the population, as well as the risk and protective factors associated with them." This study will address the question of whether and how depressive symptoms, in isolation and in combination with conduct problems, developmental processes, and social contextual risk factors, influence the development of problematic alcohol use in adolescence. The Developmental Pathways Project (DPP) is a community-based longitudinal study that aims to understand developmental trajectories for depression, and comorbid conduct problems, across the adolescent period. DPP constitutes a racially diverse sample of 521 boys and girls who were recruited as sixth graders (age 11-12) from an urban school district. The sample has been followed over the course of six years, to age 17-18. The study sample was originally stratified on psychopathology risk status, and adolescents with depressive and conduct problems were oversampled. DPP has been collecting extensive data on alcohol and other drug use since its inception and is also determining 12-month diagnoses of Alcohol Abuse and Dependence at the 12th grade (17-18 year-old) assessment. In our first aim, we will compare empirical models examining depression and conduct problems as separate main effects, as interactive, and as related to alcohol use only by virtue of common antecedents, exploring overall growth, severity, persistence, and time-sensitive effects. Aim 2 will build up a more comprehensive model of alcohol problems by incorporating developmental processes and social-contextual factors that may mediate, moderate, and have direct effects on risk for the development of alcohol problems. The third aim focuses on the role of depression and conduct problems as they relate to early initiation and transition from use to problem use. Results will have direct implications for further refining and enhancing prevention and intervention approaches to bolster their effectiveness in reducing alcohol involvement and problems among youth. PUBLIC HEALTH RELEVANCE: The consumption of alcohol by underage youth in America constitutes a public health problem with serious social, economic, and personal costs. The results of the proposed study will inform the expansion of effective prevention and treatment strategies for alcohol-related problems in adolescence. This research is responsive to NIAAA's Underage Drinking Research Initiative, as well as the Surgeon General's Call to Action to Prevent and Reduce Underage Drinking.